Discover the most starred and trending open source tools tagged with #developer-tool.
Open-source OpenAPI mock server with cloud hosting and local modes for development, testing, and CI. Generates realistic API responses from specs with latency simulation, error injection, proxy fallback, and request validation. Validated against 2,200+ real-world OpenAPI specs.
Forme is a document engine for JavaScript, written in Rust and compiled to WASM. Render the HTML and print CSS you already have, or author React, Svelte, Vue, and Preact components. Paginated PDFs in-process - no headless browser.
Run multiple Claude Code and Codex sessions in parallel — a browser terminal grid that shows which agent needs you. Local, tmux-backed, MIT.
A free, open-source developer workspace. Snippets, notes, HTTP requests, calculations, and dev tools in one local-first app.
Deterministic, local-first memory and guardrails for AI coding agents with no LLM in the hot path.
Smithers is an agentic workflow framework for defining workflows in simple TypeScript configuration files and executing them quickly, durably, and reliably
See how many times over each AI plan has paid for itself — Claude Code, Codex and the rest, priced against the published API rates, at the edge of your Mac's screen.
Lightning-fast and Powerful Code Editor written in Rust
GitComet is fastest open source user interface for GIT workflows
Stop your AI from making things up — it proposes, deterministic tools decide, every claim checked against ground truth with evidence. Grounded facts and context survive resets. Reverse engineering is the proving ground. MCP server + CLI.
Platform for AI-powered software engineers
Every coding agent in one desktop workspace. Run Claude Code, OpenAI Codex, Cursor Agent and Grok side by side. Bring your own CLI. Free during beta. Open source as of 21 September 2026 (MIT).
Semantic version control => entity-level diffs, blame, and impact analysis on top of git. 28 languages via tree-sitter. Built for coding agents.
Let your AI coding sessions talk to each other. Coordinate parallel work, exchange reviews, and hand off unfinished work between Claude Code, Codex, and other supported clients. Local-first. Independent sessions.
The why layer of repo-native project memory: the reasoning behind a codebase as Markdown in the repo, versioned by Git, for coding agents and humans, so nothing rejected is proposed twice. No database, no daemon, no account.
A native macOS terminal for agent-driven development, built on Ghostty.
Every file not opened. Every folder not explored. Tokens saved. ProjectAtlas guides coding agents with purpose metadata and an intelligent code graph, reducing token costs by over 90%.
Stop letting AI code blind. Map the architecture before every change with Birdview.
Git-native persistent memory for AI coding agents. Implements Google OKF v0.2 with sub-300µs in-memory BM25 search, embedded MCP server, and progressive disclosure. Slashes token bloat by 80% with zero external databases or dependencies. Built in pure Go.
Beautiful vim-style powerline for Claude Code